The present invention refers to a multi-purpose embossing machine for producing embossed paper.
It is known that embossing machines are designed to modify the appearance of plane and smooth sheets of paper, bestowing on them a rough, crinkled appearance or an appearance presenting patterns or motifs in relief.
At present, embossing machines are made with a structure that supports a pair of embossing assemblies set facing one another, with one on top and one underneath.
Each of said embossing assemblies comprises a steel embossing cylinder provided with protruding elements which reproduce the motifs that are to be impressed. The said cylinder is paired with another cylinder that is coated with compliant material, such as rubber, paper or leather.
The four cylinders are set aligned, with the embossing cylinders of the top embossing assembly and the bottom embossing assembly adjacent to one another.
When the machine is started, each of the two embossing assemblies is fed with a sheet which, as it passes between the embossing roller and coated roller, assumes the impression of the rollers; i.e., it is embossed. The said sheets are frequently made of paper; however, they may be made of any suitable material and different from paper.
An adhesive is laid on the two embossed sheets, and then, in the area corresponding to the area where the two embossing rollers come into contact, the sheets are set on top of one another and glued together in such a way as to obtain a paper product, such as a serviette.
Traditional embossing machines that operate according to the scheme indicated above may, in certain situations, prove far from reliable.
In fact, at times, during processing, one or both of the sheets of paper may get torn, creased, or rolled up in a ball, and may generate what in jargon is called a xe2x80x9cwigxe2x80x9d. The xe2x80x9cwigxe2x80x9d is nothing other than a mass of material of dimensions such as to obstruct or altogether prevent the passage of material between the two embossing rollers.
When this occurs, following upon the passage of the xe2x80x9cwigxe2x80x9d, one or both of the embossed rollers undergo bending and/or abrasions which damage them and render necessary subsequent operations of maintenance or replacement of the damaged elements.
In addition, in such a situation there may arise problems regarding the safety of the machine operators, linked to the possibility that pieces of material of the sheets or broken elements of the machine may be hurled out.
A purpose of the present invention is therefore to eliminate the technical drawbacks referred to above by making a multi-purpose embossing machine for producing embossed paper, which is very reliable, in particular limiting or excluding altogether all the damage due to the formation of xe2x80x9cwigsxe2x80x9d.
Another purpose of the invention is to provide an embossing machine which is very safe.
Not the least important purpose of the present invention is that of providing a multi-purpose embossing machine which is basically simple and inexpensive.
These and other purposes according to the present invention are achieved by providing a multi-purpose embossing machine for producing embossed paper, according to claim 1.
Other characteristics of the present invention are moreover defined in the ensuing claims.
Advantageously, the embossing machine according to the present invention makes it possible to facilitate and speed up considerably the operations for its maintenance. In fact, as will appear more clearly evident from what follows, the embossing machine may be opened in order to separate the two embossing assemblies in an extremely simple way and without it being necessary to dismantle the machine completely. This obviously affects costs for running and maintenance, which are reduced considerably.
Another important feature of the present invention is that it may be applied both to tip-to-tip embossing machines and to embossing machines that use the xe2x80x9cNESTEDxe2x80x9d embossing system.